Opens a stream for writing.
- iOS 2.0+
- macOS 10.1+
- tvOS 9.0+
- watchOS 2.0+
- Core Foundation
The stream to open.
stream was successfully opened,
false otherwise. If
stream is not in the
CFStream state, this function returns
Opening a stream causes it to reserve all the system resources it requires. If the stream can open in the background without blocking, this function always returns
true. To learn when a background open operation completes, you can either schedule the stream into a run loop with
CFWrite and wait for the stream’s client (set with
CFWrite) to be notified or you can poll the stream using
CFWrite, waiting for a status of